From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from newverein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 6B89821D490E2 for ; Fri, 11 Aug 2017 03:43:56 -0700 (PDT) Date: Fri, 11 Aug 2017 12:46:15 +0200 From: Christoph Hellwig Subject: Re: [PATCH v1 2/6] fs: use on-stack-bio if backing device has BDI_CAP_SYNC capability Message-ID: <20170811104615.GA14397@lst.de> References: <1502175024-28338-1-git-send-email-minchan@kernel.org> <1502175024-28338-3-git-send-email-minchan@kernel.org> <20170808124959.GB31390@bombadil.infradead.org> <20170808132904.GC31390@bombadil.infradead.org> <20170809015113.GB32338@bbox> <20170809023122.GF31390@bombadil.infradead.org> <20170809024150.GA32471@bbox> <20170810030433.GG31390@bombadil.infradead.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Dan Williams Cc: Jens Axboe , Jan Kara , linux-mm , "linux-nvdimm@lists.01.org" , Dave Chinner , Linux Kernel Mailing List , Matthew Wilcox , Christoph Hellwig , Minchan Kim , kernel-team , seungho1.park@lge.com, Andrew Morton , "karam . lee" List-ID: On Wed, Aug 09, 2017 at 08:06:24PM -0700, Dan Williams wrote: > I like it, but do you think we should switch to sbvec[] to > preclude pathological cases where nr_pages is large? Yes, please. Then I'd like to see that the on-stack bio even matters for mpage_readpage / mpage_writepage. Compared to all the buffer head overhead the bio allocation should not actually matter in practice. _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f199.google.com (mail-wr0-f199.google.com [209.85.128.199]) by kanga.kvack.org (Postfix) with ESMTP id ECEB86B0292 for ; Fri, 11 Aug 2017 06:46:16 -0400 (EDT) Received: by mail-wr0-f199.google.com with SMTP id v31so4497496wrc.7 for ; Fri, 11 Aug 2017 03:46:16 -0700 (PDT) Received: from newverein.lst.de (verein.lst.de. [213.95.11.211]) by mx.google.com with ESMTPS id k134si558857wmg.256.2017.08.11.03.46.15 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 11 Aug 2017 03:46:15 -0700 (PDT) Date: Fri, 11 Aug 2017 12:46:15 +0200 From: Christoph Hellwig Subject: Re: [PATCH v1 2/6] fs: use on-stack-bio if backing device has BDI_CAP_SYNC capability Message-ID: <20170811104615.GA14397@lst.de> References: <1502175024-28338-1-git-send-email-minchan@kernel.org> <1502175024-28338-3-git-send-email-minchan@kernel.org> <20170808124959.GB31390@bombadil.infradead.org> <20170808132904.GC31390@bombadil.infradead.org> <20170809015113.GB32338@bbox> <20170809023122.GF31390@bombadil.infradead.org> <20170809024150.GA32471@bbox> <20170810030433.GG31390@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Dan Williams Cc: Matthew Wilcox , Minchan Kim , Andrew Morton , Linux Kernel Mailing List , linux-mm , Ross Zwisler , "karam . lee" , seungho1.park@lge.com, Christoph Hellwig , Dave Chinner , Jan Kara , Jens Axboe , Vishal Verma , "linux-nvdimm@lists.01.org" , kernel-team On Wed, Aug 09, 2017 at 08:06:24PM -0700, Dan Williams wrote: > I like it, but do you think we should switch to sbvec[] to > preclude pathological cases where nr_pages is large? Yes, please. Then I'd like to see that the on-stack bio even matters for mpage_readpage / mpage_writepage. Compared to all the buffer head overhead the bio allocation should not actually matter in practice. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752844AbdHKKqR (ORCPT ); Fri, 11 Aug 2017 06:46:17 -0400 Received: from verein.lst.de ([213.95.11.211]:38305 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752616AbdHKKqQ (ORCPT ); Fri, 11 Aug 2017 06:46:16 -0400 Date: Fri, 11 Aug 2017 12:46:15 +0200 From: Christoph Hellwig To: Dan Williams Cc: Matthew Wilcox , Minchan Kim , Andrew Morton , Linux Kernel Mailing List , linux-mm , Ross Zwisler , "karam . lee" , seungho1.park@lge.com, Christoph Hellwig , Dave Chinner , Jan Kara , Jens Axboe , Vishal Verma , "linux-nvdimm@lists.01.org" , kernel-team Subject: Re: [PATCH v1 2/6] fs: use on-stack-bio if backing device has BDI_CAP_SYNC capability Message-ID: <20170811104615.GA14397@lst.de> References: <1502175024-28338-1-git-send-email-minchan@kernel.org> <1502175024-28338-3-git-send-email-minchan@kernel.org> <20170808124959.GB31390@bombadil.infradead.org> <20170808132904.GC31390@bombadil.infradead.org> <20170809015113.GB32338@bbox> <20170809023122.GF31390@bombadil.infradead.org> <20170809024150.GA32471@bbox> <20170810030433.GG31390@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 09, 2017 at 08:06:24PM -0700, Dan Williams wrote: > I like it, but do you think we should switch to sbvec[] to > preclude pathological cases where nr_pages is large? Yes, please. Then I'd like to see that the on-stack bio even matters for mpage_readpage / mpage_writepage. Compared to all the buffer head overhead the bio allocation should not actually matter in practice.